|Número de publicación||US3998678 A|
|Tipo de publicación||Concesión|
|Número de solicitud||US 05/453,031|
|Fecha de publicación||21 Dic 1976|
|Fecha de presentación||20 Mar 1974|
|Fecha de prioridad||22 Mar 1973|
|También publicado como||DE2413942A1, DE2413942B2, DE2413942C3, USB453031|
|Número de publicación||05453031, 453031, US 3998678 A, US 3998678A, US-A-3998678, US3998678 A, US3998678A|
|Inventores||Shigeo Fukase, Ushio Kawabe|
|Cesionario original||Hitachi, Ltd.|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citas de patentes (6), Otras citas (1), Citada por (149), Clasificaciones (14)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
1. Field of the Invention
The present invention relates to a method of manufacturing a thin-film field-emission electron source and, more particularly, to a method of manufacturing a thin-film field-emission electron source having a tip portion of an electron emitting area which employs evaporation and photoetching.
2. Brief Description of the Prior Art
In general, a prior-art field-emission electron source is used in a construction in which a substance to emit electrons is formed into a sharp needle-like shape and is made a cathode, while an electrode plate for acceleration is provided on the outside, so as to concentrate the electric field on the tip of the needle.
As the material of the needle-shaped cathode, a single crystal or polycrystal of tungsten is mainly used. Recently, borides such as LaB6 have also come into use.
Such a field-emission electron source, however, has the disadvantages of (1) the necessity of a superhigh vacuum (about 10- 10 Torr), (2) the necessity for a high voltage power source (several tens kV) and (3) instability in the emission current. Therefore, field emission is not widely applied as compared with the thermionic emission etc.
As a field-emission electron source free from the disadvantages, there has recently been proposed a thin-film field-emission electron source which has a sandwich structure of a substrate-metallic film-insulating film-metallic film and which has a minute cavity and a field-emitting cone within the minute cavity. Such a thin-film field-emission electron source operates at a low voltage. Since the emission source is well shielded and the concentrated electric field part is confined within the cavity, its stability increases. It is also considered that the degree of vacuum may be lower than in the prior art.
Regarding the manufacture of such a thin-film electron source in which the emitter and the accelerating anode are thin films, two methods to be explained hereunder are known.
The first method includes the step of evaporating, on a substrate of sapphire or the like, three layered films of metal - insulator - metal such as Mo - Al2 O3 - Mo. A minute cavity penetrating through the second and third layers is formed by a suitable mask evaporation process and/or etching process. In order to make a cathode with a tip in the cavity, two materials are respectively evaporated by oblique evaporation and normal evaporation. As the opening of the cavity gradually closes by oblique evaporation, the tip portion to be the emitter is created within the cavity by normal evaporation. Finally, only the material deposited by oblique evaporation is selectively dissolved and removed. Thus, an electron source is constructed.
The second method resembles the first method, but it differs in the manner of producing the tip portion. By utilizing the action of the first layer material or an additive material thinly covered on the first layer beforehand, the tip portion is precipitated or crystal-grown within the cavity by heat treatment. Although the theory underlying the method is partially unsolved in principle and is not clear, it can be employed on some types of materials. The method has the merit that a plurality of tip portions can also be formed within the cavity.
In the above two methods, the second has the greatest difficulty in that the most excellent material for the electron source with which electric fields are concentrated cannot be freely selected and used for the material of the tip portion. The materials which have been proven to be capable of forming the tip portion are of a small number.
On the other hand, the first method is not subject to the foregoing restriction concerning the material of the tip portion as in the second method, and hence, it can be said to be excellent. It has, accordingly, been considered that this method is an excellent manufacturing method for a known thin-film field-emission electron source.
In this method, however, the simultaneous evaporations of normal evaporation and oblique evaporation employed for constructing the tip portion within the cavity require an extremely high degree of precision in the method of manufacturing thin films. In particular, the necessity for the precise control of both the evaporations creates difficulty in the manufacture.
The enhancement of the manufactural yield in the first method is, therefore, subject to limitations. Where it is intended to distribute a large number of electron sources in a large area, manufacture is extremely difficult, even if possible in principle.
An object of the present invention is to eliminate the manufacturing difficulties in the prior art and, specifically, to provide a method of easily manufacturing a thin-film field-emission electron source by the combination between a conventional evaporating technique for forming a thin film and etching techniques.
In order to accomplish this object, the method of manufacturing a thin-film field-emission electron source according to the present invention comprises the various steps mentioned below. (i) A first layer film having a predetermined pattern which become cathodes and cathode wirings and which is made of an electric conductor is formed on a substrate by a well-known evaporation process, an evaporation process as well as a photoetching process, or a mask evaporation process. (ii) A second layer film of predetermined thickness which is made of an electron emissive material for use as emitters is evaporated on the entire surface of the substrate with the step (i) completed. (iii) Photoresist or electron beam-resist of a shape in which an expansion is imparted to a predetermined shape of each emitter tip portion (for example, a circle or square where the shape of the emitter tip portion is a point, and rectangle where the shape of the emitter tip portion is a straight line) is formed on the second layer film, so that at least its part may lie over the first layer film pattern for the cathode when it is viewed in the normal direction. (iv) Using a mesa etching process, the second layer film is etched from each opening portion of the resist pattern to the extent that the second layer film is sharpened in the vicinity of the middle lower part of the resist pattern and that a flat portion is partially left at the part. (v) The resist is removed, (iv) On the entire surface of the substrate with the step (v) completed, a third layer film which is made of an electrically insulating material for use as an electrode supporting structure member is evaporated to the extent that its entire area becomes above the height of the second layer film. (vii) The third layer film is polished to the extent that the surface of the third layer film becomes flat and that each tip portion of the second layer film is just exposed. (viii) On the third layer film with the step (vii) completed, at parts other than areas directly over the tops of the tip portions of the second layer film, a fourth layer metallic film of predetermined pattern for accelerating anode electrodes is formed by a well-known evaporation process and a photoetching process or by a mask evaporation process. (ix) Using as a mask the fourth layer film or a resist film remaining on the fourth layer film, only the third layer film is etched to the extent that the vicinities of the tops of the tip portions of the second layer film are exposed.
In general, an insulating material such as glass, ceramic and sapphire is used for the substrate material. However, where it is desired to form only a single electron source on one substrate, a good electrical conductor such as a metal may be employed for the substrate material. It is also possible to omit the step (i) by jointly using the substrate as the first layer film.
As the material of the first and fourth layer films, there is usually used any one of the elements of Mo, W, Ta, Re, Pt, Au, Ag, Al, Cu, Nb, Ni, Cr, Ti, Zr and Hf or an alloy containing at least two of the elements. The first layer film, however, may also be a semiconductor such as Si and Ge or a conductible compound such as various borides, nitrides and carbides (for example, LaB6).
As the material of the second layer film, there may be used the same material as the first or fourth layer film. Also useable is a boride of a rare earth element, or a solid solution thereof. Yet, also useable is a solid solution which is composed of a boride of at least one element selected from the group consisting of rare earth elements and alkaline earth metal elements such as Ca, Sr, and Ba, and a boride of a transition metal element such as Hf and Zr. Si or Ge may also be used.
As the material of the third layer film, there may be employed an insulating material such as SiO, SiO2, Al2 O3, MgO, CeO, CaF2 and MgF2.
Where the photoetching process is used for step (viii), an etchant which does not corrode the third layer film is employed as a rule. By sufficiently controlling etching conditions, however, an etchant corroding the third layer film to some extent may be used.
As an etchant at the step (ix), one is used which corrodes neither of the materials of the second and fourth layer films and which selectively etches only the third layer film.
Regarding the polshing at the step (vii), a favorable result is sometimes obtained when, in addition to a mechanical polishing, a chemical polishing is used. Where the third layer film formed by the step (vi) does not have conspicuous protuberances near the tip portions of the second layer film and has a suitable thickness, step (vii) can sometimes be omitted.
With the method of manufacturing a thin-film field-emission electron source according to the present invention constructed as explained above, the simultaneous evaporations of oblique evaporation and normal evaporation in the prior art which involve difficulty in control become unnecessary. Any evaporation is only the normal evaporation or the entire area evaporation, and is therefore very easy. Moreover, a simple apparatus suffices.
In conformity with the manufacturing method according to the present invention, previously developed, thin-film field-emission electron sources of various shapes and uses can be very easily produced without any restriction on shape and use. Furthermore, the effect of the enhancement of precision in the manufacturing process and the effect of the reduction of the proportion defective can be brought forth.
FIGS. 1(a) - 1(d) are sectional views showing steps in a prior-art method of manufacturing a thin-film field-emission electron source which uses both normal evaporation and oblique evaporation;
FIG. 2 is a perspective view of a thin-film field-emission electron source produced by a prior-art manufacturing method in which emitters are formed by heat treatment; and
FIGS. 3(a) - 3 (f) are sectional views showing steps in a method of manufacturing a thin-film field-emission electron source according to the present invention.
The methods of manufacturing thin-film field-emission electron sources by the prior art and according to the present invention will be described hereunder more in detail with reference to the accompanying drawings.
In the prior art, which jointly uses normal evaporation and oblique evaporation, a sandwich thin-film structure consisting of an Mo film as a cathode electrode 2, an Al2 O3 film as a supporting structure film 3 and an Mo film as an accelerating electrode 4 is previously formed on a ceramic insulating substrate 1 as shown in FIG. 1 (a). A cavity 5 as shown in the figure is provided in the upper layer films 3 and 4. While the substrate is being rotated, simultaneous evaporations are carried out from a vaporization source of Mo which is located on the extension of a center line normal to the film surface of the sandwich structure and passing through the center of the cavity and a vaporization source of Al2 O3 which is located at an angle of approximately 75° with respect to the center line. Then, the diameter of the opening portion of the cavity becomes smaller with a lapse of the evaporation time and the opening finally closes because as illustrated in FIG. 1 (b), the angle of incidence is so selected that vaporized molecules of Al2 O3 do not impinge on a part under the opening portion of the cavity of the accelerating electrode Mo film 4. Meanwhile, an emitter 6 of a needle-shaped projection containing Mo as its main component as shown in FIG. 1 (c) is formed in the cavity part between the Mo film 2 of the cathode electrode and the Mo film 4 of the accelerating electrode. Subsequently, a part which adheres on the Mo film 4 of the accelerating electrode and which is made of a mixture 17 consisting of Mo and Al2 O3 is chemically dissolved and removed with boiling phosphoric acid. Thus, as shown in FIG. 1 (d), an electron ray source of the plane cold cathode of the thin film structure can be obtained.
The foregoing prior-art method, however, has the following serious disadvantages:
1. Where the substrate is rotated about the center line coupling the vaporization source of Mo and the center of the cavity, it is difficult to locate the vaporization sources of Mo and Al2 O3 and the axis of rotation for preventing Al2 O3 from being mixed into the needle-shaped emitter of Mo.
2. Where the mixture consisting of alumina (Al2 O3) and Mo adhering to the Mo film of the accelerating electrode at the simultaneous evaporations is dissolved and removed with the boiling phosphoric acid, the disolving and removal of the alumina rich in Mo is comparatively difficult.
3. It is difficult to produce a plane cold cathode having a large area.
With such a manufacturing method, it is extremely difficult to mass-produce thin-film field-emission electron sources.
On the other hand, with the prior art in which a material of comparatively low melting point such as Al is deposited on the sandwich thin film structure shown in FIG. 1 (a) and, thereafter, a needle-like emitter is grown within the cavity 5 by heat treatment, a thin-film field-emission electron source as shown in FIG. 2 is obtained. The greatest difficulty of this manufacturing method is, as already set forth, that a material of excellent electron emissivity cannot be freely selected for the emitter.
The steps of the method of manufacturing a thin-film field-emission electron source according to the present invention will now be explained with reference to FIGS. 3 (a) - 3 (f).
First of all, a first-layer metallic film 8 is evaporated on a substrate 7 (of, for example, glass, ceramic or sapphire). Since the film 8 is to be used as cathodes or a cathode wiring pattern, it may be a good electrical conductor, and it may also be a semiconductor or any other suitable compound. In such a case where a plurality of electron sources are formed and the respective electron sources are used independently, the film 8 must form a pattern. In this case, the evaporation is a mask evaporation, or the pattern is formed by photoetching techniques after evaporation.
Subsequently, a second-layer film 9 is evaporated over the entire area. FIG. 3 (a) shows this state. Since the film 9 is worked into tip portions and constitutes the principal part of each electron source, an electron emissive material is used for the film 9.
Next, a resist film 10 (of photoresist or electron beam resist) is applied, exposed to light and developed.
In conformity with the shape of each tip portion to be formed, the resist film 10 remaining has a pattern with a width imparted to a point or line, that is, a circular, square or rectangular pattern. This pattern and the wiring pattern of the film 8 must overlap at least partially when viewed in a direction normal to the films. Otherwise, the tip portion may not be connected with the cathode. Only the film 9 is subjected to mesa etching through the resist film 10, and the etching stops when the film 9 is shaped sharply at its tip portions. This state is shown in FIG. 3 (b).
Subsequently, as shown in FIG. 3 (c), the resist film 10 is removed, and a third layer film 11 is evaporated over the entire area. A material for the third layer film 11 must be an electric insulator. The thickness of the film 11 is made sufficiently large, so as to prevent the bottom part of each dent from becoming lower than the extremity of the tip portion 9. Otherwise, inferior insulation may result. The film 11 may be formed by sputtering or vapor growth, not by evaporation. The film 11 has a protuberance in the vicinity of each tip portion 9, which protuberance interferes with subsequent steps. It is, therefore, polished and flattened as shown in FIG. 3 (d). The polishing is stopped immediately before the tip portion 9 is exposed.
Where the protuberance in the vicinity of the tip portion 9 is not conspicuous and the thickness of the film 11 is suitable, the polishing step can be sometimes omitted. As is well known, the polishing is well finished in some cases when a chemical polishing is used in addition to a mechanical polishing. Subsequently, a fourth layer film 12 is evaporated. Since the film 12 is used for an accelerating anode of each electron source, a good electrical conductor is employed therefor. Further, the film 12 is etched by the photoetching process so that, as illustrated in FIG. 3 (e), the vicinity of the top of the tip portion 9 may be removed. At this stage, the third layer film exposed between the respectively adjacent accelerating electrodes 12 may be under-etched at the same time. At this time, at etchant which does not corrode the film 11 may be employed.
However, if the control of etching conditions is satisfactorily made, even at etchant corroding the film to some extent can be used. It is also possible that, by mask-evaporating the film 12, the pattern is formed without carrying out the etching.
Subsequently, using an etching which corrodes neither of the materials of the film 12 and the tip portion 9 and which selectively etches only the film 11, the film 11 is etched to a slightly overetched extent, to expose the tip portion 9. Thus, a thin-film field-emission electron source shown in FIG. 3 (f) is completed.
In this manner, according to the method of the invention, all the evaporations can employ a one-source evaporation. Therefore, the evaporations are not extremely easy, but also can be effected with a simple apparatus. It is a matter of course that a plurality of vaporization sources may be used in order to employ a film material of a poly-element system. As is apparent from the above explanation, mask evaporation is sometimes applicable because, although it cannot attain sufficient precision as compared with the etching technique, it can simplify the stages of manufacture. Lastly, regarding the step of the polishing the thin film, a variety of known methods may be applied.
The thin film field-emission electron sources which can be produced by the manufacturing method according to the present invention, include the following:
i. A single point electron source which has a rectangular, square or circular opening portion and in which the top of the tip portion of the second layer film is dot-like.
ii. A single line electron source which has an opening portion of a rectangle or the like shape and in which the top of the tip portion of the second layer film is linear.
iii. A composite electron source in which a plurality of point electron sources or line electron sources are arrayed so as to be regularly or irregularly distributed.
iv. In the composite electron source, a composite electron source in which wirings are so made that the respective electron sources can be independently driven by independently applying fields to the respective emitters.
v. In the composite electron source capable of the independent drive, a composite electron source of long life in which at least one emitter is used as the first electron source and another emitter is made a spare electron source for exchange.
vi. A plane electron source in which a number of point electron sources or line electron sources are arranged in an array.
vii. An electron source for panel display or for pattern display in which a number of point electron sources or line electron sources capable of the independent drive are arrayed.
viii. A composite electron source in which a number of line electron sources are arrayed in parallel, said each line electron source being so constructed that the top of the tip portion of the second layer film is rectilinear.
ix. An electron source for display adapted to emit electrons in a curved manner, in which the top of the tip portion of the second layer film is curvilinear and which has an opening portion corresponding thereto.
Hereunder will be described a concrete embodiment of the method of manufacturing a thin-film field-emission electron source according to the present invention.
A sapphire plate 1 mm thick was used as a substrate. Mo was evaporated thereon to a thickness of about 0.2μm at a substrate temperature of approximately 500°C by an electron beam, and was made a first-layer cathode film. Subsequently, by making the substrate temperature 800°C for employing a sintered compact of an intermetallic compound LaB6 as a raw material, a second layer LaB6 film having a thickness of 2μm was deposited by electron beam evaporation.
Using an aqueous solution of nitric acid as an etchant and by a photoresist process, etching was carried out so that single electron source-projections whose tips were dot-like could be formed at intervals of 5 mm. Al2 O3 was evaporated to a thickness 2.5 - 3 μm at a substrate temperature of 500°C again by the electron beam evaporation. The surface of the Al2 O3 film was lightly polished by, for example, lapping with a diamond paste, and was flattened. Further, Mo was evaporated to 0.2μm at a substrate temperature of 500°C. Thereafter, Mo over the tip portions was etched by the use of the aqueous solution of nitric acid, to form an accelerating electrode film. Next, the Al2 O3 film was dissolved with a heated solution of phosphoric acid, to expose the tip portions. Further, scribing was performed so that the electron sources might be substantially centered, and the substrate was divided into the individual electron sources. Finally, the entire structure was subjected to a heat treatment of 1000°C at 30 minutes in a vacuum furnace. Thus, the thin film point electron source of LaB6 was completed.
The electron source was mounted on the part of a filament for an electron microscope. With a voltage of 220V applied between the accelerating electrode and the cathode, the electronic current was measured. Then, an emission current of 100μA was obtained. When the source was operated continuously for 100 hours under this state, no change was noted in characteristics. The emission current was sufficinently stable, the brightness of an image was found to be several times higher than in the case of a prior-art thermal filament, and the resolution was enhanced. When the tip portion was observed by a scanning electron microscope, it was revealed to have a curvature of approximately 0.1μm.
As understood also from this embodiment, the thin film field-emission electron source has many merits such as an increase brightness, reducing the size, lowering the supply voltage and making the life long.
Especially, it does not require heating unlike a thermionic source, and is therefore suitable to uses of quick response as an electron source of instantaneous lighting.
|Patente citada||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US3475664 *||2 Sep 1965||28 Oct 1969||Texas Instruments Inc||Ambient atmosphere isolated semiconductor devices|
|US3506506 *||14 Jul 1967||14 Abr 1970||Ibm||Capacitor defect isolation|
|US3531857 *||26 Jul 1967||6 Oct 1970||Hitachi Ltd||Method of manufacturing substrate for semiconductor integrated circuit|
|US3665241 *||13 Jul 1970||23 May 1972||Stanford Research Inst||Field ionizer and field emission cathode structures and methods of production|
|US3700510 *||9 Mar 1970||24 Oct 1972||Hughes Aircraft Co||Masking techniques for use in fabricating microelectronic components|
|US3755704 *||6 Feb 1970||28 Ago 1973||Stanford Research Inst||Field emission cathode structures and devices utilizing such structures|
|1||*||IBM Tech. Discl. Bulletin, "Fabricating Monolithic Circuits," J. Gardiner et al., vol. 10, No. 5, Oct. 1967, pp. 655-656.|
|Patente citante||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US4291068 *||31 Oct 1978||22 Sep 1981||The United States Of America As Represented By The Secretary Of The Army||Method of making semiconductor photodetector with reduced time-constant|
|US4301369 *||13 Feb 1979||17 Nov 1981||The President Of Osaka University||Semiconductor ion emitter for mass spectrometry|
|US4302700 *||7 Dic 1979||24 Nov 1981||International Business Machines Corporation||Electrode guide for metal paper printers|
|US4307507 *||10 Sep 1980||29 Dic 1981||The United States Of America As Represented By The Secretary Of The Navy||Method of manufacturing a field-emission cathode structure|
|US4418283 *||17 Nov 1980||29 Nov 1983||Thomson-Csf||Microlithographic system using a charged particle beam|
|US4498952 *||17 Sep 1982||12 Feb 1985||Condesin, Inc.||Batch fabrication procedure for manufacture of arrays of field emitted electron beams with integral self-aligned optical lense in microguns|
|US4513308 *||23 Sep 1982||23 Abr 1985||The United States Of America As Represented By The Secretary Of The Navy||p-n Junction controlled field emitter array cathode|
|US4721885 *||11 Feb 1987||26 Ene 1988||Sri International||Very high speed integrated microelectronic tubes|
|US4728851 *||8 Ene 1982||1 Mar 1988||Ford Motor Company||Field emitter device with gated memory|
|US4766340 *||2 Mar 1987||23 Ago 1988||Mast Karel D V D||Semiconductor device having a cold cathode|
|US4818914 *||17 Jul 1987||4 Abr 1989||Sri International||High efficiency lamp|
|US4857161 *||7 Ene 1987||15 Ago 1989||Commissariat A L'energie Atomique||Process for the production of a display means by cathodoluminescence excited by field emission|
|US4908539 *||24 Mar 1988||13 Mar 1990||Commissariat A L'energie Atomique||Display unit by cathodoluminescence excited by field emission|
|US4943343 *||14 Ago 1989||24 Jul 1990||Zaher Bardai||Self-aligned gate process for fabricating field emitter arrays|
|US4956574 *||8 Ago 1989||11 Sep 1990||Motorola, Inc.||Switched anode field emission device|
|US4964946 *||2 Feb 1990||23 Oct 1990||The United States Of America As Represented By The Secretary Of The Navy||Process for fabricating self-aligned field emitter arrays|
|US4968382 *||12 Ene 1990||6 Nov 1990||The General Electric Company, P.L.C.||Electronic devices|
|US4973378 *||27 Feb 1990||27 Nov 1990||The General Electric Company, P.L.C.||Method of making electronic devices|
|US4975656 *||31 Mar 1989||4 Dic 1990||Litton Systems, Inc.||Enhanced secondary electron emitter|
|US5007873 *||9 Feb 1990||16 Abr 1991||Motorola, Inc.||Non-planar field emission device having an emitter formed with a substantially normal vapor deposition process|
|US5019003 *||29 Sep 1989||28 May 1991||Motorola, Inc.||Field emission device having preformed emitters|
|US5030921 *||9 Feb 1990||9 Jul 1991||Motorola, Inc.||Cascaded cold cathode field emission devices|
|US5055077 *||22 Nov 1989||8 Oct 1991||Motorola, Inc.||Cold cathode field emission device having an electrode in an encapsulating layer|
|US5064396 *||29 Ene 1990||12 Nov 1991||Coloray Display Corporation||Method of manufacturing an electric field producing structure including a field emission cathode|
|US5079476 *||9 Feb 1990||7 Ene 1992||Motorola, Inc.||Encapsulated field emission device|
|US5126287 *||7 Jun 1990||30 Jun 1992||Mcnc||Self-aligned electron emitter fabrication method and devices formed thereby|
|US5136764 *||27 Sep 1990||11 Ago 1992||Motorola, Inc.||Method for forming a field emission device|
|US5138237 *||20 Ago 1991||11 Ago 1992||Motorola, Inc.||Field emission electron device employing a modulatable diamond semiconductor emitter|
|US5141459 *||21 Feb 1992||25 Ago 1992||International Business Machines Corporation||Structures and processes for fabricating field emission cathodes|
|US5142184 *||9 Feb 1990||25 Ago 1992||Kane Robert C||Cold cathode field emission device with integral emitter ballasting|
|US5148078 *||29 Ago 1990||15 Sep 1992||Motorola, Inc.||Field emission device employing a concentric post|
|US5156705 *||10 Sep 1990||20 Oct 1992||Motorola, Inc.||Non-homogeneous multi-elemental electron emitter|
|US5157309 *||13 Sep 1990||20 Oct 1992||Motorola Inc.||Cold-cathode field emission device employing a current source means|
|US5162704 *||5 Feb 1992||10 Nov 1992||Futaba Denshi Kogyo K.K.||Field emission cathode|
|US5163328 *||6 Ago 1990||17 Nov 1992||Colin Electronics Co., Ltd.||Miniature pressure sensor and pressure sensor arrays|
|US5176557 *||14 Ago 1991||5 Ene 1993||Canon Kabushiki Kaisha||Electron emission element and method of manufacturing the same|
|US5194780 *||31 May 1991||16 Mar 1993||Commissariat A L'energie Atomique||Electron source with microtip emissive cathodes|
|US5199918 *||7 Nov 1991||6 Abr 1993||Microelectronics And Computer Technology Corporation||Method of forming field emitter device with diamond emission tips|
|US5201681 *||9 Mar 1992||13 Abr 1993||Canon Kabushiki Kaisha||Method of emitting electrons|
|US5203731 *||5 Mar 1992||20 Abr 1993||International Business Machines Corporation||Process and structure of an integrated vacuum microelectronic device|
|US5211707 *||11 Jul 1991||18 May 1993||Gte Laboratories Incorporated||Semiconductor metal composite field emission cathodes|
|US5218273 *||25 Ene 1991||8 Jun 1993||Motorola, Inc.||Multi-function field emission device|
|US5219310 *||13 Mar 1992||15 Jun 1993||Sony Corporation||Method for producing planar electron radiating device|
|US5220725 *||18 Ago 1992||22 Jun 1993||Northeastern University||Micro-emitter-based low-contact-force interconnection device|
|US5229331 *||14 Feb 1992||20 Jul 1993||Micron Technology, Inc.||Method to form self-aligned gate structures around cold cathode emitter tips using chemical mechanical polishing technology|
|US5245248 *||9 Abr 1991||14 Sep 1993||Northeastern University||Micro-emitter-based low-contact-force interconnection device|
|US5252833 *||5 Feb 1992||12 Oct 1993||Motorola, Inc.||Electron source for depletion mode electron emission apparatus|
|US5281890 *||30 Oct 1990||25 Ene 1994||Motorola, Inc.||Field emission device having a central anode|
|US5312514 *||23 Abr 1993||17 May 1994||Microelectronics And Computer Technology Corporation||Method of making a field emitter device using randomly located nuclei as an etch mask|
|US5334908 *||23 Dic 1992||2 Ago 1994||International Business Machines Corporation||Structures and processes for fabricating field emission cathode tips using secondary cusp|
|US5341063 *||24 Nov 1992||23 Ago 1994||Microelectronics And Computer Technology Corporation||Field emitter with diamond emission tips|
|US5371431 *||4 Mar 1992||6 Dic 1994||Mcnc||Vertical microelectronic field emission devices including elongate vertical pillars having resistive bottom portions|
|US5372973 *||27 Abr 1993||13 Dic 1994||Micron Technology, Inc.||Method to form self-aligned gate structures around cold cathode emitter tips using chemical mechanical polishing technology|
|US5374868 *||11 Sep 1992||20 Dic 1994||Micron Display Technology, Inc.||Method for formation of a trench accessible cold-cathode field emission device|
|US5397957 *||10 Nov 1992||14 Mar 1995||International Business Machines Corporation||Process and structure of an integrated vacuum microelectronic device|
|US5399238 *||22 Abr 1994||21 Mar 1995||Microelectronics And Computer Technology Corporation||Method of making field emission tips using physical vapor deposition of random nuclei as etch mask|
|US5401676 *||30 Ago 1993||28 Mar 1995||Samsung Display Devices Co., Ltd.||Method for making a silicon field emission device|
|US5430292 *||12 Oct 1993||4 Jul 1995||Fujitsu Limited||Pattern inspection apparatus and electron beam apparatus|
|US5445550 *||22 Dic 1993||29 Ago 1995||Xie; Chenggang||Lateral field emitter device and method of manufacturing same|
|US5455196 *||17 Mar 1994||3 Oct 1995||Texas Instruments Incorporated||Method of forming an array of electron emitters|
|US5461280 *||10 Feb 1992||24 Oct 1995||Motorola||Field emission device employing photon-enhanced electron emission|
|US5463269 *||6 Mar 1992||31 Oct 1995||International Business Machines Corporation||Process and structure of an integrated vacuum microelectronic device|
|US5465024 *||24 Feb 1992||7 Nov 1995||Motorola, Inc.||Flat panel display using field emission devices|
|US5469014 *||3 Feb 1992||21 Nov 1995||Futaba Denshi Kogyo Kk||Field emission element|
|US5475280 *||30 Ago 1994||12 Dic 1995||Mcnc||Vertical microelectronic field emission devices|
|US5496200 *||14 Sep 1994||5 Mar 1996||United Microelectronics Corporation||Sealed vacuum electronic devices|
|US5528099 *||26 Ene 1995||18 Jun 1996||Microelectronics And Computer Technology Corporation||Lateral field emitter device|
|US5529524 *||5 Jun 1995||25 Jun 1996||Fed Corporation||Method of forming a spacer structure between opposedly facing plate members|
|US5534743 *||7 Sep 1994||9 Jul 1996||Fed Corporation||Field emission display devices, and field emission electron beam source and isolation structure components therefor|
|US5536193 *||23 Jun 1994||16 Jul 1996||Microelectronics And Computer Technology Corporation||Method of making wide band gap field emitter|
|US5548181 *||5 Jun 1995||20 Ago 1996||Fed Corporation||Field emission device comprising dielectric overlayer|
|US5557105 *||11 Oct 1994||17 Sep 1996||Fujitsu Limited||Pattern inspection apparatus and electron beam apparatus|
|US5561339 *||7 Sep 1994||1 Oct 1996||Fed Corporation||Field emission array magnetic sensor devices|
|US5569973 *||6 Jun 1995||29 Oct 1996||International Business Machines Corporation||Integrated microelectronic device|
|US5580380 *||30 Ene 1995||3 Dic 1996||North Carolina State University||Method for forming a diamond coated field emitter and device produced thereby|
|US5583393 *||24 Mar 1994||10 Dic 1996||Fed Corporation||Selectively shaped field emission electron beam source, and phosphor array for use therewith|
|US5587623 *||3 Abr 1996||24 Dic 1996||Fed Corporation||Field emitter structure and method of making the same|
|US5600200 *||7 Jun 1995||4 Feb 1997||Microelectronics And Computer Technology Corporation||Wire-mesh cathode|
|US5601966 *||7 Jun 1995||11 Feb 1997||Microelectronics And Computer Technology Corporation||Methods for fabricating flat panel display systems and components|
|US5607335 *||29 Jun 1994||4 Mar 1997||Silicon Video Corporation||Fabrication of electron-emitting structures using charged-particle tracks and removal of emitter material|
|US5608283 *||29 Jun 1994||4 Mar 1997||Candescent Technologies Corporation||Electron-emitting devices utilizing electron-emissive particles which typically contain carbon|
|US5612712 *||7 Jun 1995||18 Mar 1997||Microelectronics And Computer Technology Corporation||Diode structure flat panel display|
|US5614353 *||7 Jun 1995||25 Mar 1997||Si Diamond Technology, Inc.||Methods for fabricating flat panel display systems and components|
|US5619097 *||5 Jun 1995||8 Abr 1997||Fed Corporation||Panel display with dielectric spacer structure|
|US5629583 *||28 Mar 1996||13 May 1997||Fed Corporation||Flat panel display assembly comprising photoformed spacer structure, and method of making the same|
|US5632664 *||28 Sep 1995||27 May 1997||Texas Instruments Incorporated||Field emission device cathode and method of fabrication|
|US5647785 *||13 Sep 1995||15 Jul 1997||Mcnc||Methods of making vertical microelectronic field emission devices|
|US5648698 *||2 Jun 1995||15 Jul 1997||Nec Corporation||Field emission cold cathode element having exposed substrate|
|US5650688 *||2 Jun 1995||22 Jul 1997||Nec Corporation||Field emission cold cathode element having exposed substrate|
|US5652083 *||7 Jun 1995||29 Jul 1997||Microelectronics And Computer Technology Corporation||Methods for fabricating flat panel display systems and components|
|US5660570 *||10 Mar 1995||26 Ago 1997||Northeastern University||Micro emitter based low contact force interconnection device|
|US5662815 *||31 Jul 1995||2 Sep 1997||Samsung Display Devices Co., Ltd.||Fabricating method of a multiple micro-tip field emission device using selective etching of an adhesion layer|
|US5663608 *||17 Abr 1996||2 Sep 1997||Fed Corporation||Field emission display devices, and field emisssion electron beam source and isolation structure components therefor|
|US5675216 *||7 Jun 1995||7 Oct 1997||Microelectronics And Computer Technololgy Corp.||Amorphic diamond film flat field emission cathode|
|US5686791 *||7 Jun 1995||11 Nov 1997||Microelectronics And Computer Technology Corp.||Amorphic diamond film flat field emission cathode|
|US5688158 *||24 Ago 1995||18 Nov 1997||Fed Corporation||Planarizing process for field emitter displays and other electron source applications|
|US5693235 *||4 Dic 1995||2 Dic 1997||Industrial Technology Research Institute||Methods for manufacturing cold cathode arrays|
|US5696028 *||2 Sep 1994||9 Dic 1997||Micron Technology, Inc.||Method to form an insulative barrier useful in field emission displays for reducing surface leakage|
|US5703435 *||23 May 1996||30 Dic 1997||Microelectronics & Computer Technology Corp.||Diamond film flat field emission cathode|
|US5711694 *||26 Jun 1996||27 Ene 1998||Texas Instruments Incorporated||Field emission device with lattice vacancy, post-supported gate|
|US5755944 *||7 Jun 1996||26 May 1998||Candescent Technologies Corporation||Formation of layer having openings produced by utilizing particles deposited under influence of electric field|
|US5766446 *||5 Mar 1996||16 Jun 1998||Candescent Technologies Corporation||Electrochemical removal of material, particularly excess emitter material in electron-emitting device|
|US5780960 *||18 Dic 1996||14 Jul 1998||Texas Instruments Incorporated||Micro-machined field emission microtips|
|US5793154 *||7 Jun 1995||11 Ago 1998||Futaba Denshi Kogyo K.K.||Field emission element|
|US5813892 *||12 Jul 1996||29 Sep 1998||Candescent Technologies Corporation||Use of charged-particle tracks in fabricating electron-emitting device having resistive layer|
|US5827099 *||7 Dic 1995||27 Oct 1998||Candescent Technologies Corporation||Use of early formed lift-off layer in fabricating gated electron-emitting devices|
|US5828163 *||13 Ene 1997||27 Oct 1998||Fed Corporation||Field emitter device with a current limiter structure|
|US5828288 *||24 Ago 1995||27 Oct 1998||Fed Corporation||Pedestal edge emitter and non-linear current limiters for field emitter displays and other electron source applications|
|US5831378 *||25 Ago 1997||3 Nov 1998||Micron Technology, Inc.||Insulative barrier useful in field emission displays for reducing surface leakage|
|US5844351 *||24 Ago 1995||1 Dic 1998||Fed Corporation||Field emitter device, and veil process for THR fabrication thereof|
|US5851669 *||22 May 1995||22 Dic 1998||Candescent Technologies Corporation||Field-emission device that utilizes filamentary electron-emissive elements and typically has self-aligned gate|
|US5861707 *||7 Jun 1995||19 Ene 1999||Si Diamond Technology, Inc.||Field emitter with wide band gap emission areas and method of using|
|US5864199 *||18 Ago 1997||26 Ene 1999||Advanced Micro Devices, Inc.||Electron beam emitting tungsten filament|
|US5865657 *||7 Jun 1996||2 Feb 1999||Candescent Technologies Corporation||Fabrication of gated electron-emitting device utilizing distributed particles to form gate openings typically beveled and/or combined with lift-off or electrochemical removal of excess emitter material|
|US5865659 *||7 Jun 1996||2 Feb 1999||Candescent Technologies Corporation||Fabrication of gated electron-emitting device utilizing distributed particles to define gate openings and utilizing spacer material to control spacing between gate layer and electron-emissive elements|
|US5886460 *||20 Nov 1997||23 Mar 1999||Fed Corporation||Field emitter device, and veil process for the fabrication thereof|
|US5893967 *||30 Jun 1997||13 Abr 1999||Candescent Technologies Corporation||Impedance-assisted electrochemical removal of material, particularly excess emitter material in electron-emitting device|
|US5900301 *||3 Ene 1997||4 May 1999||Candescent Technologies Corporation||Structure and fabrication of electron-emitting devices utilizing electron-emissive particles which typically contain carbon|
|US5902165 *||10 Jul 1996||11 May 1999||Texas Instruments Incorporated||Field emission device with over-etched gate dielectric|
|US5903098 *||6 Ene 1997||11 May 1999||Fed Corporation||Field emission display device having multiplicity of through conductive vias and a backside connector|
|US5903243 *||6 Ene 1997||11 May 1999||Fed Corporation||Compact, body-mountable field emission display device, and display panel having utility for use therewith|
|US5913704 *||12 May 1997||22 Jun 1999||Candescent Technologies Corporation||Fabrication of electronic devices by method that involves ion tracking|
|US6010918 *||10 Feb 1998||4 Ene 2000||Fed Corporation||Gate electrode structure for field emission devices and method of making|
|US6019658 *||11 Sep 1998||1 Feb 2000||Candescent Technologies Corporation||Fabrication of gated electron-emitting device utilizing distributed particles to define gate openings, typically in combination with spacer material to control spacing between gate layer and electron-emissive elements|
|US6022256 *||6 Nov 1996||8 Feb 2000||Micron Display Technology, Inc.||Field emission display and method of making same|
|US6066507 *||14 Oct 1997||23 May 2000||Micron Technology, Inc.||Method to form an insulative barrier useful in field emission displays for reducing surface leakage|
|US6120674 *||30 Jun 1997||19 Sep 2000||Candescent Technologies Corporation||Electrochemical removal of material in electron-emitting device|
|US6127773 *||4 Jun 1997||3 Oct 2000||Si Diamond Technology, Inc.||Amorphic diamond film flat field emission cathode|
|US6181060||13 Jul 1998||30 Ene 2001||Micron Technology, Inc.||Field emission display with plural dielectric layers|
|US6187603||7 Jun 1996||13 Feb 2001||Candescent Technologies Corporation||Fabrication of gated electron-emitting devices utilizing distributed particles to define gate openings, typically in combination with lift-off of excess emitter material|
|US6204596 *||30 Jun 1998||20 Mar 2001||Candescent Technologies Corporation||Filamentary electron-emission device having self-aligned gate or/and lower conductive/resistive region|
|US6555402||8 Feb 2002||29 Abr 2003||Micron Technology, Inc.||Self-aligned field extraction grid and method of forming|
|US6566804 *||7 Sep 1999||20 May 2003||Motorola, Inc.||Field emission device and method of operation|
|US6617863 *||2 Abr 1999||9 Sep 2003||Hitachi, Ltd.||Probing device and manufacturing method thereof, as well as testing apparatus and manufacturing method of semiconductor with use thereof|
|US6629869||7 Jun 1995||7 Oct 2003||Si Diamond Technology, Inc.||Method of making flat panel displays having diamond thin film cathode|
|US6833232||8 Ene 2003||21 Dic 2004||Dongbu Electronics Co., Ltd.||Micro-pattern forming method for semiconductor device|
|US6900646||10 Abr 2002||31 May 2005||Hitachi, Ltd.||Probing device and manufacturing method thereof, as well as testing apparatus and manufacturing method of semiconductor with use thereof|
|US6911154 *||21 Dic 2001||28 Jun 2005||Commissariat A L'energie Atomique||Method for manufacturing a cathode with an aligned extraction grid and focusing grid|
|US6963160||26 Dic 2001||8 Nov 2005||Trepton Research Group, Inc.||Gated electron emitter having supported gate|
|US20020114882 *||21 Dic 2001||22 Ago 2002||Christophe Bourcheix||Method for manufacturing a cathode with an aligned extraction grid and focusing grid|
|US20020135387 *||10 Abr 2002||26 Sep 2002||Susumu Kasukabe||Probing device and manufacturing method thereof, as well as testing apparatus and manufacturing method of semiconductor with use thereof|
|US20120052246 *||31 Oct 2011||1 Mar 2012||Northwestern University||Mesoscale pyramids, arrays and methods of preparation|
|EP0234989A1 *||21 Ene 1987||2 Sep 1987||Commissariat A L'energie Atomique||Method of manufacturing an imaging device using field emission cathodoluminescence|
|WO1991005363A1 *||17 Sep 1990||18 Abr 1991||Motorola Inc||Flat panel display using field emission devices|
|WO1991012627A1 *||18 Ene 1991||22 Ago 1991||Motorola Inc||Field emission device encapsulated by substantially normal vapor deposition|
|WO1992002030A1 *||17 Oct 1990||6 Feb 1992||Ibm||Process and structure of an integrated vacuum microelectronic device|
|WO1996006442A2 *||9 Ago 1995||29 Feb 1996||Fed Corp||Body-mountable field emission display device|
|WO1998031044A2 *||13 Ene 1998||16 Jul 1998||Fed Corp||A field emitter device with a current limiter structure|
|WO1999040600A2 *||10 Feb 1999||12 Ago 1999||Fed Corp||Gate electrode structure for field emission devices and method of making|
|Clasificación de EE.UU.||216/11, 427/259, 427/266, 427/77, 313/309, 445/24, 216/41, 427/264, 313/336, 216/100|
|Clasificación cooperativa||H01J9/025, H01J2201/30457|